In Night at the Museum, Ben Stiller signs up as a security guard at New York's Natural History Museum, a post which offers low pay, anti-social hours, and a magical Egyptian tablet which brings all the exhibits to life after dark. Suddenly he has to deal with a waxwork Attila The Hun, a pride of stuffed lions and a dinosaur skeleton which wants to play "fetch". Like Snakes On A Plane, the film has the kind of cracking, all-in-the-title concept which seems like it can't go wrong ... except when the director of Cheaper By The Dozen and the writers of Herbie: Fully Loaded are around. In their hands, the exhibits come alive, but the movie doesn't.

There are enough silly gags and celebrity cameos to ensure that Night at the Museum isn't the worst way to pass an afternoon at the cinema. Stiller has invited his friends to the party, so Owen Wilson and Steve Coogan pop up as inch-high models of a cowboy and a Roman legionary, while Ricky Gervais plays the museum's manager in a three-piece suit and a bow tie - because that, of course, is what Englishmen always wear to work. But the various fun bits and pieces are just that - bits and pieces. They never coalesce into a story, and it's only in the last half hour that a plot creaks into motion, courtesy of Dick Van Dyke, Mickey Rooney and Bill Cobbs as three superannuated night-watchmen.

What's worse is that the film-makers do everything they can to drain away any air of danger and awe from the concept. First, they establish that the exhibits' nocturnal walkabout has been happening for 50 years; presumably, the museum closes early in the winter. Second, they spread the action over three successive nights. Stiller's first night at the museum lasts about 15 minutes and by the morning we've already seen the lions, the Huns, the dinosaur, and everything else there is to see.

And third, they give us a hero who barely bats an eyelid at what's going on. He's more worried about whether his son respects him than whether he'll be torn limb from limb by a 1,600-year-old European warlord.

It's another example of how 21st-century Hollywood can twist the most inappropriate scenario into a schmaltzy lesson in parenthood.

What you want from Night at the Museum is homicidal statues and marauding taxidermy. What you get is an ex-wife chiding, "I don't think Nicky has any room in his heart for more disappointment."